Formation and internal structure of Tamarix cones in the Taklimakan Desert

The distribution, formative process, and internal structures of Tamarix cones located in the southern part of the Taklimakan Desert were investigated over 3 years (from 1993 to 1995). Typical dunes were excavated in order to observe the internal structures of Tamarix cones. The main results obtained can be summarized as follows:•cones have developed on piedmont alluvial fans, low river terraces, and areas between oases and moving sand dunes;•The climate of the study area is extremely arid, with a windy season from March to July. During the windy season, sand materials are transported by the frequent storms and accumulated around the spp. clumps, resulting in a sand layer. In the autumn, the vegetation like spp. drops leaves that form a litter layer overlaying the sand layer. There are many sticky nodules along the leaves of spp., so fallen leaves stick together and form a cohesive litter layer. As a result, a sand layer and a litter layer form alternately once a year. If this process continues, for several years, a cone can be formed and developed;•The excavated cross-sections of cones are composed of alternating sand layers and litter layers. The thickness of both layers differ within the cross section. Layers are thicker in the central part around the trunk of the bush than in the outer part;•In the upper part of the cross section, the organic materials of the layers are very fresh, but they are decomposed in the lower parts due to the increased moisture content and the load of overlaying layers.